io faccio cosi...

if CFiscale<>"" then
if ((Len(CFiscale)<16) OR (Len(CFiscale)>16)) then
test=0
ErroreCFisc=1
else
rem ----------------------------------
remcontrollo il check del CFiscale
rem ----------------------------------
SDalCF="0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z"
SPari="0,1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25"
SDispari="1,0,5,7,9,13,15,17,19,21,1,0,5,7,9,13,15,17,19,21,2,4,18,20,11,3,6,8,12,14,16,10,22,25,24,23"
SCControllo="A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z"
Dim DalCF, Pari, Dispari, CControllo
DalCF = Split(SDalCF, ",", -1, 1)
Pari = Split(SPari, ",", -1, 1)
Dispari = Split(SDispari, ",", -1, 1)
CControllo = Split(SCControllo, ",", -1, 1)
Dim CodiceFiscale ()
For k = 0 to 15
Redim Preserve CodiceFiscale(k)
CodiceFiscale(k)=Mid(CFiscale, k+1, 1)
next
OrdineCarattere=1
Somma=0
For i = 0 to 14
Carattere=CodiceFiscale(i)
IDCarattere=0
for n=0 to 35
if UCase(DalCF(n))=UCase(Carattere) then
IDCarattere=n
end if
next
if OrdineCarattere=1 then
Somma=Somma + CInt(Dispari(IDCarattere))
OrdineCarattere=2
else
Somma=Somma + CInt(Pari(IDCarattere))
OrdineCarattere=1
end if
next
CheckC=Somma-(26*(Int(Somma/26)))
if UCase(CodiceFiscale(15))<>UCase(CControllo(CheckC)) then
test=0
ErroreCFisc=1
end if
end if
end if

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